Key Facts

—The project. Rio Metro Line 3 would be the state’s first intercity line, linking the capital to Niterói and São Gonçalo under Guanabara Bay.

—The scale. The preliminary route spans about 50 km with roughly 29 stations, reaching Itaboraí.

—The time saving. A Coppe/UFRJ study estimates an Icaraí–Santos Dumont trip would drop from about 75 minutes to 11, an 85 percent cut.

—The demand. Earlier projections put daily ridership for the corridor at around 650,000 passengers.